Congress enacted the Marine Protection, Research, and Sanctuaries Act (MPRSA) in 1972.

One of the perennial problems facing humans involves determining what to do with our waste products. Humans produce many different types of unwanted materials, including sewage, solid waste such as trash and the by-products of industrial processes. In many cases, these waste products can be harmful to the environment. In order to offer some protection to our coastal waters and the world’s oceans, Congress in 1972 passed legislation designed to "prevent or strictly limit the dumping into ocean waters of any material that would adversely affect human health, welfare, or amenities, or the marine environment, ecological systems, or economic potentialities." These restrictions apply both to U.S. flag vessels and to vessels traveling in U.S. waters. Since the enactment of this legislation, the cleanliness of United States coastal waters has improved.

Xpeditions
In Aquarium Habitats (3–5), students consider how aquariums can provide realistic habitats for marine animals. They use the Internet to "visit" three aquarium habitats and determine whether these aquariums succeed in providing high-quality environments for the animals that live in them. Students conclude by designing unique aquarium habitats based on what they have learned.  

In Changing with the Tide (3–5), students learn about and act out the functions of the salt marsh habitat. They learn about the changing nature of salt marshes, and they imitate the actions of the plants and animals that live there in order to understand life in the salt marsh. 

Science NetLinks
The Science Update Marine Reserves (3–12) focuses on the preservation of marine ecosystems through the creation of marine reserves. Students learn about the many challenges and benefits of the creation of the undersea preserves and, in the process, gain an understanding not only of the need for conservation, but also of the need to balance ecological concerns with the needs of man.

In Marine Sanctuaries (6–8), students learn about the national marine sanctuaries found in the Pacific and Atlantic oceans and off the coast of American Samoa. They include breeding and feeding grounds of whales, sea lions, sharks and sea turtles; significant coral reefs and kelp forest habitats; and the remains of the U.S.S. Monitor, a Civil War ironclad sunk off the coast of North Carolina.  

Oceans (6–8) helps students to have a better perception of Earth's oceans and to understand Earth's water cycle. The two-fold lesson begins with an experiment that demonstrates water evaporating and coming back down. Through several additional activities, students learn that water in the ocean evaporates into the atmosphere and comes back down as precipitation.